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COMPLETE SPECIFICATIONS.
Efficiency.
Heating.
brush holder brackets to the engine castings. In case the latter is necessary, however, the expense for such attachment will be borne by the Contractor.
Proposition No. 2. On three generators of the same design as called for in proposition No. i, but to run at 250 revolutions per minute.
Proposition No. J. On three 200 kilowatt generators of the same design as called for in Proposition No. i, but to run at a speed of 100 revolutions per minute.
Proposition No. 4. On three 200 kilowatt generators to run at a speed of So revolutions per minute. Same design and conditions as Proposition No. i.
Proposition No. j. On three generators of the same design, but to have a capacity of 150 kilowatts, and to run at a speed of 150 revolutions per minute.
Proposition No. 6. On three generators of 150 kilowatt capacity each, to run at a speed of 250 revolutions per minute.
Proposition No. 7. On three 150 kilowatt generators similar to those called for under Proposition No. i, but to run at 100 revolutions per minute.
Proposition No. 8. On three 150 Kilowatt generators similar to those called for under Proposition No. i, but to run at So revolutions per minute.
The Contractor shall state in each proposition the efficiency his generators will give, and it must be in the form of a guarantee.
By efficiency is meant the result that is obtained by dividing the total energy in kilowatts delivered on the switchboard of the station by the mechanical horse power delivered to the armature of the generator, due allowance being made for the loss in the mains leading from the generator brushes to the switchboard. The power delivered to the armature shall be taken as the indicated horse power in the cylinders of the engine, as measured by the engine indicator, less the indicated power required to drive the engine and generator running light or with no load.
The generators shall be capable of giving their full capacity for a period of 18 hours in continuous operation without serious sparking at the brushes, and without raising the temperature of the arm a-